body{
  margin: 0;
  padding: 0;
}

#top-image {
  background: linear-gradient(
      rgba(0, 0, 0, 0.2),
      rgba(0, 0, 0, 0.2)
  ), url('../images/gz.jpeg') no-repeat fixed;
  position:fixed ;
  top:0;
  width:100%;
  z-index:0;
  height:100%;
}

